The purpose of this program project is the study of the mechanisms of cardiovascular disease so as to improve diagnosis, therapy and provide means for more accurate assessment and follow-up. There are three major areas of emphasis: 1) Longitudinal study of the mechanisms and therapy of arrhythmias, 2) Hemodynamic, metabolic, electrocardiographic and myocardial blood flow correlates of coronary artery disease and, 3) Non-invasive techniques in the study of cardiovascular disease. It is the aim of this program project to foster integration, application of information and innovation in the above areas through the interactions of personnel and provision of core facilities.